Enodeb and ue for dynamic cell on and off

ABSTRACT

Disclosed in some examples are methods, systems, and machine readable mediums which reuse existing LTE functionality to rapidly signal UEs on the availability of a LTE-U cell. Using these techniques the on/off operation can be in the order of a few milliseconds (ms). Several techniques are disclosed herein, including use of component carrier (CC) specific Discontinuous Reception (DRX) signaling, PDCCH signaling, DL assignment based signaling, Physical Hybrid Automatic Repeat Request Indicator Channel (PHICH) signaling, Beacon signaling, and the like.

PRIORITY CLAIM

This application is a continuation of U.S. patent application Ser. No.14/554,221, filed Nov. 26, 2014, which claims the benefit of priority,under 35 U.S.C. Section 119 to U.S. Provisional Patent Application Ser.No. 61/968,281, entitled “METHODS FOR DYNAMIC CELL ON/OFF INLICENSE/UNLICENSE SPECTRUM” filed on Mar. 20, 2014 to Seunghee Han etal, which are incorporated by reference in their entirety.

TECHNICAL FIELD

Embodiments pertain to wireless technologies. Some embodiments relate toco-existence of differing wireless technologies.

BACKGROUND

Mobile devices utilizing high speed data connections based upon LongTerm Evolution (LTE) and Long Term Evolution-Advanced (LTE-A) continueto increase in popularity. These mobile devices offer users the abilityto download richer content and better user experiences on the go. Forexample, users may stream high definition videos, stream high qualitymusic, play network games, download applications, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numeralsmay describe similar components in different views. Like numerals havingdifferent letter suffixes may represent different instances of similarcomponents. The drawings illustrate generally, by way of example, butnot by way of limitation, various embodiments discussed in the presentdocument.

FIG. 1 shows an example timeline showing DRX availability, as determinedby the parameters onDurationTimer and LongDRXCycle and a timeline ofS-Cell availability according to some examples of the presentdisclosure.

FIG. 2A shows a diagram of using the PDCCH of the P-Cell to indicateavailability of the S-Cell according to some examples of the presentdisclosure.

FIG. 2B shows a diagram of using the PDCCH of the P-Cell to indicateavailability of the S-Cell according to some examples of the presentdisclosure.

FIG. 3 shows a diagram of using scheduling to indicate availability ofthe S-Cell according to some examples of the present disclosure.

FIG. 4 shows a flowchart of a method of an eNodeB for indicating thatthe S-Cell is on or off is shown according to some examples of thepresent disclosure.

FIG. 5 shows a flowchart of a method performed by a UE of being notifiedof S-Cell availability is shown according to some examples of thepresent disclosure.

FIG. 6 shows a flowchart of a method performed by a UE to performcarrier specific DRX on an S-Cell is shown according to some examples ofthe present disclosure.

FIG. 7 shows a flowchart of a method performed by a UE to determineS-Cell availability is shown according to some examples of the presentdisclosure.

FIG. 8 shows a flowchart of a method performed by a UE to determineS-Cell availability is shown according to some examples of the presentdisclosure.

FIG. 9 shows a flowchart of a method performed by a UE to determineS-Cell availability is shown according to some examples of the presentdisclosure.

FIG. 10 shows a logical schematic of an eNodeB and a UE according tosome examples of the present disclosure.

FIG. 11 is a block diagram illustrating an example of a machine uponwhich one or more embodiments may be implemented.

DETAILED DESCRIPTION

The increased demand for these mobile devices puts increasing pressureon wireless carriers to meet the demands of their increasing user base.Despite increasing efficiencies in using the existing licensed frequencyspectrums for wireless technologies such as Universal MobileTelecommunications (UMTS), LTE, and LTE-A, carriers are finding itdifficult to meet demand for data services with their current bandwidthallocations.

LTE-Unlicensed (LTE-U) is an effort to utilized unlicensed spectrum,such as the Industrial, Scientific, and Medical (ISM) band. The goal isto increase the capacity of LTE networks through the use of thesefrequency bands. LTE-U features smaller cells with lower transmit poweras compared to a standard LTE cell. In some examples, LTE-U may utilizecarrier aggregation to aggregate co-located licensed and unlicensedcells. Carrier aggregation enables multiple LTE carriers to be usedtogether to provide high data rates for 4G LTE Advanced.

While LTE-U offers the potential to increase the available bandwidth ofLTE networks in order to better serve the increasing demands for mobiledata, the spectrum used for LTE-U is shared with other communicationprotocols. In some examples, networks such as those operating inaccordance with an Institute for Electronics and Electrical Engineers(IEEE) 802.11 standard (commonly referred to as Wi-Fi), those operatingin accordance with a Bluetooth standard, those operating in accordancewith an IEEE 802.15 standard (commonly referred to as ZigBee), andothers may operate in these spectrum bands. In some examples, in orderto avoid interference, the LTE-U network and the other networks in thesefrequency bands may time-divide the spectrum. That is, each network willhave a portion of time (e.g., a time slot, time slice, or time window)during which that network has exclusive access to the medium. In otherexamples, the eNodeB (the base station) which provides the LTE-U cell,may monitor the medium for periods in which the medium is experiencinglighter traffic, and provide the LTE-U cell in those periods.

The goal in implementing LTE-U is to reuse existing LTE functionality toreduce implementation time and complexity. However, in order toimplement this time-multiplexing scheme, the LTE-U cell operating in theunlicensed spectrum must be switched on and off relatively quickly.Existing LTE functionality for signaling this to User Equipment (UE) istoo slow.

Disclosed in some examples are methods, systems, and machine readablemediums which reuse existing LTE functionality or require only minorchanges to the LTE specification to rapidly signal UEs on theavailability of a LTE-U cell. Using these techniques the on/offoperation may be in the order of a few milliseconds (ms). Severaltechniques are disclosed herein, including use of component carrier (CC)specific Discontinuous Reception (DRX) signaling, Physical DownlinkControl Channel (PDCCH) signaling, Downlink (DL) assignment basedsignaling, Physical Hybrid Automatic Repeat Request Indicator Channel(PHICH) signaling, Beacon signaling, and the like. As used herein theterm Primary Cell or P-Cell is used to refer to a cell on the licensedfrequency band, and the Secondary Cell or S-Cell is used to refer to acell on the unlicensed frequency band. In some examples, the P-Cell andthe S-Cell may include any number and combination of channels. Examplechannels may include control channels such as a PDCCH, data channelssuch as a Physical Downlink Shared Channel (PDSCH), PHICH channels, oneor more beacon channels, or the like.

In some examples, for more dynamic operations (e.g., sub-frame),multiple indicators can be used in a hierarchy of indicators. Forexample, a second level of S-Cell availability indicator (or triggering)by the PDCCH (discussed below) can be applied and the second level ofindicator (e.g., by the PDCCH) can override the first level indicator(e.g., DRX indicators).

Use of DRX Functionality

In some examples the availability of the LTE-U cell may be signaledthrough the modification of power saving techniques which put a mobiledevice to sleep. For example, DRX in LTE allows the UE to monitor thePDCCH at predetermined time periods rather than continuously. Monitoringthe PDCCH at these predetermined time periods saves the UE's battery asopposed to monitoring the PDCCH continuously. In LTE, DRX is applied ina UE specific fashion—that is, the mobile is awake or asleep for allcarriers a UE is associated with. In some examples, the DRX capabilitiesalready present in LTE may be applied to the S-Cell carriers only.

In some examples, the eNodeB can determine the time periods for whichthe LTE-U cell is to be available. For example, the eNodeB maycoordinate with other users of the unlicensed spectrum, either throughdirect messaging, or through medium sensing. The eNodeB may setup theUE's DRX parameters to coincide with the periods of S-Cell availability.For example, the UE may be awake and monitoring the PDCCH of the S-Cellwhen the S-Cell is available and may be in a DRX sleep period when theS-Cell is not available.

DRX parameters may include onDurationTimer which may be the number offrames over which the UE reads the PDCCH every DRX cycle before going tosleep. onDurationTimer thus specifies the length of time the UE remainsawake once awoken. The DRX parameter LongDRXCycle is the duration of the“On” time defined by onDurationTimer plus the sleep time.

FIG. 1 shows an example timeline 1000 showing DRX availability, asdetermined by the parameters onDurationTimer and LongDRXCycle and atimeline of S-Cell availability according to some examples of thepresent disclosure. As shown in FIG. 1, onDurationTimer specifies alength of time in which the UE is awake at 1010 and 1020, and in someexamples, this can coincide with the time in which the S-Cell isavailable on the unlicensed spectrum 1030 and 1040. When the UE is awakethe UE can monitor the PDCCH, receive the Physical Downlink SharedChannel (PDSCH), measure Channel State Information (CSI), and/or performRadio Resource Management (RRM) measurements for the S-Cell. At timeperiod 1050 the UE is asleep. When the UE is asleep, the UE will notmonitor channels/signals for the S-Cell carrier (and in some examples,for the primary cell (P-Cell) as well) and can thus sleep. This alsocorresponds to the time the S-Cell is not available at 1060. In someexamples, the UE may be awake and monitoring the PDCCH, receive thePhysical Downlink Shared Channel (PDSCH), measuring Channel StateInformation (CSI), and/or performing Radio Resource Management (RRM)measurements for the P-Cell. During the period in which the S-Cell isnot available, the S-Cell may be turned off. The LongDRXCycle 1070specifies the entire DRX cycle and is calculated as the time the UE isawake+the time the UE is asleep. In FIG. 1, while the time the UE wasawake coincided exactly with the time the S-Cell was available and thetime the UE was asleep coincided exactly with the time the S-Cell wasnot available, in other examples, the UE may be awake for only part ofthe S-Cell availability.

Use of PDCCH

In carrier aggregation, multiple carriers are used to increase bandwidthwhile still maintaining compatibility with older devices. In someexamples, the P-Cell and the S-Cell may be aggregated. When carrieraggregation is used there are two possible mechanisms for scheduling theS-Cell. In one possibility, called same carrier scheduling, each carrierschedules its own resources using its own PDCCH. In another possibility,called cross carrier scheduling, resources from the S-Cell are scheduledon the PDCCH on the P-Cell.

In some examples, an S-Cell is turned on or off by information fields inthe PDCCH transmitted on the P-Cell (cross carrier scheduling), or byinformation fields in the PDCCH transmitted on the S-Cell (same carrierscheduling). The information field may be a simple binary 1 or 0 and mayindicate that the S-Cell is available (or not available) currently, orduring a particular period of time in the future.

In some examples, a particular field may be inserted into the PDCCH thatindicates that the S-Cell is available or not. In other examples, one ormore Radio Network Temporary Identifiers (RNTI) may be selected thatconvey this information. The RNTI is used to scramble a CyclicRedundancy Check field of the PDCCH. Using a particular RNTI mayindicate that the S-Cell is available, and the absence of the particularRNTI may indicate that the S-Cell is not-available. In other examples aparticular RNTI may indicate that the S-Cell is not available and theabsence of the particular RNTI may indicate that the S-Cell isavailable. In yet other examples, a particular RNTI may indicate thatthe S-Cell is available and a different RNTI may indicate that theS-Cell is not available.

In other examples, the S-Cell availability may be indicated by whetherthe eNodeB schedules the Physical Downlink Shared Channel (PDSCH) forthe S-Cell, either on the P-Cell (cross-carrier scheduling) or theS-Cell (same carrier scheduling).

FIG. 2A shows a diagram 2000 of using the PDCCH of the P-Cell toindicate availability of the S-Cell according to some examples of thepresent disclosure. The PDCCH on the P-Cell carrier 2010 indicateswhether the S-Cell carrier 2020 is on or off. In some examples, eachtime period 2030-2050 may be a particular unit of time (e.g., 10milliseconds, 1 frame, and the like). At time unit 2030, the S-Cell ison and the P-Cell indicates this in the PDCCH. For example, a bit-fieldin the PDCCH may indicate whether the S-Cell On or Off. In otherexamples a particular RNTI value may be used to scramble the PDCCH CRCto indicate that the S-Cell is ON. At time unit 2040, the S-Cell is off,and the P-Cell indicates this in the PDCCH. For example, a bit-field inthe PDCCH may indicate whether the S-Cell On or Off. In other examples aparticular RNTI value may be used to scramble the PDCCH CRC to indicatethat the S-Cell is OFF. At time unit 2050, the S-Cell is on and theP-Cell indicates this in the PDCCH. For example, a bit-field in thePDCCH may indicate whether the S-Cell On or Off. In other examples aparticular RNTI value may be used to scramble the PDCCH CRC to indicatethat the S-Cell is ON.

FIG. 2B shows a diagram 2100 of using the PDCCH of the P-Cell toindicate availability of the S-Cell according to some examples of thepresent disclosure. The PDCCH on the P-Cell carrier 2110 indicateswhether the S-Cell carrier 2120 is on or off. In contrast to the examplein FIG. 2A, the PDCCH of the P-Cell 2110 indicates the status of theS-Cell for a future time period. Shown in FIG. 2B, the future timeperiod is the next time period, but in other examples, the indicator inthe PDCCH of the P-Cell for the current time period may indicate S-Cellavailability one or more time periods in the future. These examples maygive the UE extra time to switch from the P-Cell to the S-Cell and back.In FIG. 2B, at time unit 2130, the S-Cell is on, however, the P-Cellindicates that the S-Cell is off for time period 2140. The indicator inthe PDCCH may be the same indicators discussed above with respect toFIG. 2A. At time unit 2140, the S-Cell is off, but the P-Cell indicatesthat the S-Cell is on for time period 2150.

In some examples, the indication may be transmitted in any PDCCHtransmitted from either the P-Cell or the S-Cell. For example, theS-Cell indication may be transmitted on a PDCCH transmitted on theP-Cell that is scheduling resources on the P-Cell. In another example,the S-Cell indication may be transmitted on a PDCCH scheduling resourceson the S-Cell and either transmitted on the P-Cell or the S-Cell. Insome examples, if the UE cannot receive an indication from the PDCCH, orcannot decode the PDCCH, the UE may assume the S-Cell is off.

While FIGS. 2A and 2B showed a single transmission of the indicator forindicating the available/unavailability of the S-Cell, in otherexamples, the indicator may be transmitted multiple times. This mayreduce the false alarm detection due to a CRC error. For example, if aUE detects different indications for the S-Cell in the same time period,the UE may assume that the S-Cell is off to avoid unnecessary activityon the S-Cell during a period in which it may be unavailable (e.g.,avoids unnecessary Channel State Information/Radio Resource Messagingmeasurements).

In some examples, a hybrid approach for FIGS. 2A and 2B may be employedwhereby the PDCCH on the P-Cell may have indicators on the status of theS-Cell for both the current and a future time period.

Downlink Assignment (e.g., an (E)PDCCH) Indicators

Another indicator for the S-Cell status that may be used is thescheduling status in a sub-frame. The scheduling status of the sub-framemay implicitly indicate that the scheduled cell is turned on in asub-frame. If there is scheduling (i.e., the PDCCH exists from thescheduling cell) on the scheduled cell in a sub-frame, the cell isactive in that sub-frame. If there is no scheduling (i.e., no PDCCH fromthe scheduling cell) on the scheduled cell in a sub-frame, the cell maybe unavailable during that sub-frame.

In some examples, different types of PDDCHs can be defined for differentpurposes. For example, a first PDCCH may be used to schedule PDSCHresources, and a second PDCCH may be used to indicate the sub-frame forCSI and/or RRM measurements (i.e., the cell in the sub-frame is turnedon to transmit some signals to facilitate CSI/RRM measurements). Thismay be applicable to both self and cross carrier indications. Anexplicit bitfield may indicate on or off states—in this case the PDCCHwill be present. If semi-persistent scheduling (SPS) is configured forthe S-Cell, at every sub-frame conveying the SPS PDSCH without thecorresponding PDCCH the cell can be regarded as ON automatically.

FIG. 3 shows a diagram 3000 of using scheduling to indicate availabilityof the S-Cell according to some examples of the present disclosure. Attime period 3030 the P-Cell schedules the PDSCH (Physical DownlinkShared Channel) or the E-PDSCH for the S-Cell and thus the S-Cell isavailable for that period. At time period 3040 the P-Cell does notschedule anything for the PDSCH or the enhanced PDSCH (EPDSCH) for theS-Cell, and thus the S-Cell is not available for that period. At timeperiod 3040 the P-Cell once again schedules the PDSCH or the EPDSCH forthe S-Cell and thus the S-Cell is available for that period.

In some examples, the occurrence of the PDDCCH and the scheduled PDSCHmay indicate a current availability of the S-Cell or may indicate anavailability of the S-Cell in a future timeframe, similar to FIG. 2B.

PHICH Based Indicator

In some examples the Physical Hybrid-Automatic Repeat Request IndicatorChannel (PHICH) may be used as an indicator for the availability of theS-Cell. The PHICH may be transmitted from the P-Cell or the S-Cell. Theuse of the PHICH channel as an indicator is similar to using thedownlink assignment but using the PHICH channel. One of ordinary skillin the art with the benefit of Applicants' disclosure will appreciatethat many different types of channels may be utilized.

For more dynamic operations (e.g., sub-frame), in some examples,multiple indicators can be used in a hierarchy of indicators. Forexample, a second level of S-Cell availability indicator (or triggering)by the PDCCH (discussed below) can be applied and the second level ofindicator (e.g., by the PDCCH) can override the first level indicator(e.g., DRX indicators).

In some examples, the occurrence of the indicator on the PHICH mayindicate a current availability of the S-Cell or may indicate anavailability of the S-Cell in a future timeframe, similar to FIG. 2B.

Beacon Signal Based Indicators

In some examples various beacon signals may be utilized to indicatewhether the S-Cell is available or not. In some examples, the presenceor absence of the beacon signal may convey the availability ornon-availability of the beacon signals. In other examples, the beaconsignals may contain the indicator (e.g., a bit indicator). Examplebeacon signals can include one or more of: Primary SynchronizationSignal (PSS), Secondary Synchronization Signal (SSS), Cell SpecificReference Signal (CRS), Channel State Information Reference Signals(CSI-RS), Positioning Reference Signals (PRS), or Discovery ReferenceSignal (DRS).

In some examples, if the beacon signal transmission time and frequencyis predetermined or configured, the presence of the beacon at that time(e.g., at time unit N) indicates that the S-Cell is available at N+K,where K=0, 1, 2 . . . . In some examples, K may be predetermined, or inother examples K may be configurable.

Method and System Descriptions

Turning now to FIG. 4 a flowchart of a method 4000 of an eNodeB forindicating that the S-Cell is on or off is shown according to someexamples of the present disclosure. At operation 4010 the eNodeB mayprovide a primary cell (P-Cell). At operation 4020 the eNodeB maydetermine that the S-Cell frequency band is available to provide anS-Cell. This may be for the current time period, or for a future timeperiod. The eNodeB may determine that the S-Cell frequency band is freebased upon a time scheduling algorithm in which the eNodeB has certaintime periods in which it may operate the S-Cell. In other examples theeNodeB may determine the medium is free by sensing for traffic on themedium. At operation 4030 the eNodeB may send an indication to the UEthat the S-Cell is available. As already noted, this indication may takemany forms. For example, the indication may be a DRX indication, a PDCCHindication, a scheduling indication, a beacon signal indication a PHICHindication and the like. At operation 4040 the eNodeB may provide theS-Cell during the determined availability.

Turning now to FIG. 5, a flowchart of a method 5000 performed by a UE ofbeing notified of S-Cell availability is shown according to someexamples of the present disclosure. At operation 5010 the UE mayassociate with the P-Cell. At operation 5020 the UE may receive anindication that the S-Cell frequency band is available. As already notedthis indication may take many forms. For example, the indication may bea DRX indication, a PDCCH indication, a scheduling indication, a beaconsignal indication, a PHICH indication and the like. At operation 5030the UE may utilize the S-Cell.

Turning now to FIG. 6, a flowchart of a method 6000 performed by a UE toperform carrier specific DRX on an S-Cell is shown according to someexamples of the present disclosure. At operation 6010 the UE may receiveDRX parameters from the eNodeB. These parameters may be received overeither the S-Cell or P-Cell. For example, on the PDCCH. In someexamples, these parameters may include LongDRXCycle and OnDurationTimer.At operation 6020, once the start of the first active period of the DRXperiod begins, the UE may set the OnDurationTimer 6020. At operation6030 the UE may utilize the S-Cell. Once OnDurationTimer expires atoperation 6040, the UE may switch back to the P-Cell or may go to sleep.The UE may also set a timer that is equal to theLongDRXCycle-onDurationTimer to set the timer for the next wake period.At operation 6060 this timer expires and the flow diagram may transitionto repeating operations 6020-6060.

Turning now to FIG. 7, a flowchart of a method 7000 performed by a UE todetermine S-Cell availability is shown according to some examples of thepresent disclosure. At operation 7010 the UE may receive the PDCCH oneither the P-Cell or the S-Cell. At operation 7020 the UE may decode theS-Cell availability from the PDCCH. In some examples, the S-Cellavailability may be determined by examining one or more fields in thePDCCH. In other examples, the RNTI used to decode the CRC bits mayindicate whether the S-Cell is active or not. If the S-Cell isdetermined to be active at operation 7030, the UE may utilize the S-Cellfor the indicated period 7040. If the S-Cell is not active, the UE maygo back to normal operations, including receiving the PDCCH at operation7010. Once the indicated period is over, the UE may also return tonormal operations at operation 7010.

Turning now to FIG. 8, a flowchart of a method 8000 performed by a UE todetermine S-Cell availability is shown according to some examples of thepresent disclosure. At operation 8010 the UE may receive the PDCCH oneither the P-Cell or the S-Cell. At operation 8020 the UE may decode theS-Cell availability by determining if the UE is scheduled on the S-Cell.If the S-Cell is determined to be active at operation 8030, the UE mayutilize the S-Cell for the indicated period 8040. If the S-Cell is notactive, the UE may go back to normal operations, including receiving thePDCCH at operation 8010. Once the indicated period is over, the UE mayalso return to normal operations at operation 8010.

Turning now to FIG. 9, a flowchart of a method 9000 performed by a UE todetermine S-Cell availability is shown according to some examples of thepresent disclosure. At operation 9010 the UE may receive a beacon signalon either the P-Cell or the S-Cell. At operation 9020 the UE may decodethe S-Cell availability using information in the beacon as previouslyexplained. If the S-Cell is determined to be active at operation 9030,the UE may utilize the S-Cell for the indicated period 9040. If theS-Cell is not active, the UE may go back to normal operations, includingsearching for the beacon at operation 9010. Once the indicated period isover, the UE may also return to normal operations at operation 9010.

Turning now to FIG. 10, a logical schematic of an eNodeB 10010 and a UE10020 is shown according to some examples of the present disclosure.eNodeB 10010 and UE 10020 may communicate over P-Cell connection 10090and/or S-Cell connection 10100. eNodeB 10010 includes a control module10030. Control module 10030 may coordinate providing an indication ofS-Cell availability or unavailability to one or more UEs (such as UE10020), providing a P-Cell, an S-Cell, and the like. Control module10030 may determine when the S-Cell is available and may instruct othermodules (e.g., P-Cell module 10040 and S-Cell module 10050) to transmitan indication of availability of the S-Cell to the UE according to anyof the methods disclosed herein for providing a notification to the UE.In some examples, control module 10030 may determine one or more carrierspecific (e.g., S-Cell specific) DRX parameters for one or more UEs(such as UE 10020) such that the UE is awake at time periods whichcoincide with the availability of the S-Cell. eNodeB 10010 may includeP-Cell module 10040, which may provide the P-Cell, including any PDCCHchannels, PDSCH channels, pilot channels, PHICH channels, beaconsignals, and the like. S-Cell module 10050 may provide the S-Cell,including any PDCCH channels, PDSCH channels, pilot channels, PHICHchannels, beacon signals, and the like.

UE 10020 may include a control module 10060 which may coordinate betweenutilizing the P-Cell and the S-Cell, as well as determining S-Cellavailability. P-Cell module 10070 may associate with and communicatewith eNodeB 10010 over the P-Cell 10090. P-Cell module 10070 may decodethe PDCCH, beacon signals, PHICH, scheduling information, DRXinformation, and the like. S-Cell module 10080 may associate with andcommunicate with eNodeB 10010 over the S-Cell 10100. S-Cell module 10080may decode the PDCCH, beacon signals, PHICH, scheduling information, DRXinformation, and the like. P-Cell module 10070 and S-Cell module 10080may pass the indications received (e.g., DRX information, PDCCHindications, beacon signals, PHICH information, and the like) to controlmodule 10060. Control module 10060 may determine based upon theindications if the S-Cell is available and in some examples, when theS-Cell is available. Control module 10060 may also configure the UEbased upon any DRX parameters received. For example, control module10060 may set one or more timers to wake and sleep the UE. In someexamples, the control module may determine whether the UE is associatedwith the eNodeB through the P-Cell or S-Cell.

P-Cell modules 10040, 10070 may implement one or more layers of aprotocol stack, including Physical (PHY) layers, Medium Access Control(MAC) layers, Radio Link Control, Packet Data Convergence Protocols, andthe like for the P-Cell. S-Cell modules 10050, 10080 may implement oneor more layers of a protocol stack, including Physical (PHY) layers,Medium Access Control (MAC) layers, Radio Link Control, Packet DataConvergence Protocols, and the like for the S-Cell. In some examples,the eNodeB 10010 and the UE may operate in accordance with a Long TermEvolution (LTE) family of standards promulgated by the 3^(rd) GenerationPartnership Project (3GPP). Other example protocols that the UE andeNodeB may operate according to include a Universal MobileTelecommunications Systems (UMTS), a Global System for MobileCommunications (GSM) and the like.

FIG. 11 illustrates a block diagram of an example machine 11000 uponwhich any one or more of the techniques (e.g., methodologies) discussedherein may perform. In alternative embodiments, the machine 11000 mayoperate as a standalone device or may be connected (e.g., networked) toother machines. In a networked deployment, the machine 11000 may operatein the capacity of a server machine, a client machine, or both inserver-client network environments. In an example, the machine 11000 mayact as a peer machine in peer-to-peer (P2P) (or other distributed)network environment. The machine 11000 may be a UE, eNodeB, personalcomputer (PC), a tablet PC, a set-top box (STB), a personal digitalassistant (PDA), a mobile telephone, a smart phone, a web appliance, anetwork router, switch or bridge, or any machine capable of executinginstructions (sequential or otherwise) that specify actions to be takenby that machine. The machine 11000 may implement any one of the modulesof FIG. 10. Further, while only a single machine is illustrated, theterm “machine” shall also be taken to include any collection of machinesthat individually or jointly execute a set (or multiple sets) ofinstructions to perform any one or more of the methodologies discussedherein, such as cloud computing, software as a service (SaaS), othercomputer cluster configurations.

Examples, as described herein, may include, or may operate on, logic ora number of components, modules, or mechanisms. Modules are tangibleentities (e.g., hardware) capable of performing specified operations andmay be configured or arranged in a certain manner. In an example,circuits may be arranged (e.g., internally or with respect to externalentities such as other circuits) in a specified manner as a module. Inan example, the whole or part of one or more computer systems (e.g., astandalone, client or server computer system) or one or more hardwareprocessors may be configured by firmware or software (e.g.,instructions, an application portion, or an application) as a modulethat operates to perform specified operations. In an example, thesoftware may reside on a machine readable medium. In an example, thesoftware, when executed by the underlying hardware of the module, causesthe hardware to perform the specified operations.

Accordingly, the term “module” is understood to encompass a tangibleentity, be that an entity that is physically constructed, specificallyconfigured (e.g., hardwired), or temporarily (e.g., transitorily)configured (e.g., programmed) to operate in a specified manner or toperform part or all of any operation described herein. Consideringexamples in which modules are temporarily configured, each of themodules need not be instantiated at any one moment in time. For example,where the modules comprise a general-purpose hardware processorconfigured using software, the general-purpose hardware processor may beconfigured as respective different modules at different times. Softwaremay accordingly configure a hardware processor, for example, toconstitute a particular module at one instance of time and to constitutea different module at a different instance of time.

Machine (e.g., computer system) 11000 may include a hardware processor11002 (e.g., a central processing unit (CPU), a graphics processing unit(GPU), a hardware processor core, or any combination thereof), a mainmemory 11004 and a static memory 11006, some or all of which maycommunicate with each other via an interlink (e.g., bus) 11008. Themachine 11000 may further include a display unit 11010, an alphanumericinput device 11012 (e.g., a keyboard), and a user interface (UI)navigation device 11014 (e.g., a mouse). In an example, the display unit11010, input device 11012 and UI navigation device 11014 may be a touchscreen display. The machine 11000 may additionally include a storagedevice (e.g., drive unit) 11016, a signal generation device 11018 (e.g.,a speaker), a network interface device 11020, and one or more sensors11021, such as a global positioning system (GPS) sensor, compass,accelerometer, or other sensor. The machine 11000 may include an outputcontroller 11028, such as a serial (e.g., universal serial bus (USB),parallel, or other wired or wireless (e.g., infrared (IR), near fieldcommunication (NFC), etc.) connection to communicate or control one ormore peripheral devices (e.g., a printer, card reader, etc.).

The storage device 11016 may include a machine readable medium 11022 onwhich is stored one or more sets of data structures or instructions11024 (e.g., software) embodying or utilized by any one or more of thetechniques or functions described herein. The instructions 11024 mayalso reside, completely or at least partially, within the main memory11004, within static memory 11006, or within the hardware processor11002 during execution thereof by the machine 11000. In an example, oneor any combination of the hardware processor 11002, the main memory11004, the static memory 11006, or the storage device 11016 mayconstitute machine readable media.

While the machine readable medium 11022 is illustrated as a singlemedium, the term “machine readable medium” may include a single mediumor multiple media (e.g., a centralized or distributed database, and/orassociated caches and servers) configured to store the one or moreinstructions 11024.

The term “machine readable medium” may include any medium that iscapable of storing, encoding, or carrying instructions for execution bythe machine 11000 and that cause the machine 11000 to perform any one ormore of the techniques of the present disclosure, or that is capable ofstoring, encoding or carrying data structures used by or associated withsuch instructions. Non-limiting machine readable medium examples mayinclude solid-state memories, and optical and magnetic media. Specificexamples of machine readable media may include: non-volatile memory,such as semiconductor memory devices (e.g., Electrically ProgrammableRead-Only Memory (EPROM), Electrically Erasable Programmable Read-OnlyMemory (EEPROM)) and flash memory devices; magnetic disks, such asinternal hard disks and removable disks; magneto-optical disks; RandomAccess Memory (RAM); Solid State Drives (SSD); and CD-ROM and DVD-ROMdisks. In some examples, machine readable media may includenon-transitory machine readable media. In some examples, machinereadable media may include machine readable media that is not atransitory propagating signal.

The instructions 11024 may further be transmitted or received over acommunications network 11026 using a transmission medium via the networkinterface device 11020. The Machine 11000 may communicate with one ormore other machines utilizing any one of a number of transfer protocols(e.g., frame relay, internet protocol (IP), transmission controlprotocol (TCP), user datagram protocol (UDP), hypertext transferprotocol (HTTP), etc.). Example communication networks may include alocal area network (LAN), a wide area network (WAN), a packet datanetwork (e.g., the Internet), mobile telephone networks (e.g., cellularnetworks), Plain Old Telephone (POTS) networks, and wireless datanetworks (e.g., Institute of Electrical and Electronics Engineers (IEEE)802.11 family of standards known as Wi-Fi®, IEEE 802.16 family ofstandards known as WiMax®), IEEE 802.15.4 family of standards, a LongTerm Evolution (LTE) family of standards, a Universal MobileTelecommunications System (UMTS) family of standards, peer-to-peer (P2P)networks, among others. In an example, the network interface device11020 may include one or more physical jacks (e.g., Ethernet, coaxial,or phone jacks) or one or more antennas to connect to the communicationsnetwork 11026. In an example, the network interface device 11020 mayinclude a plurality of antennas to wirelessly communicate using at leastone of single-input multiple-output (SIMO), multiple-inputmultiple-output (MIMO), or multiple-input single-output (MISO)techniques. In some examples, the network interface device 11020 maywirelessly communicate using Multiple User MIMO techniques.

Other Notes and Examples

Example 1 includes subject matter (such as a method, means forperforming acts, machine readable medium that stores instructions whichwhen performed by a machine, cause the machine to perform operations)for signaling a User Equipment (UE) when a cell is available in anunlicensed frequency band comprising: providing a primary cell (P-Cell)on a licensed frequency band; determining that an unlicensed frequencyband is available for use by a secondary cell (S-Cell) for a determinedtime window; sending an indication to the UE that the unlicensedfrequency band is available for use by the S-Cell, the indicationsignaling the UE that the frequency band is available for use by the UEfor at least a portion of the determined time window; and providing theS-Cell in the frequency band for the determined time window.

In example 2, the subject matter of example 1 may optionally includewherein the indication is a Radio Resource Control (RRC) messagespecifying a Discontinuous Reception (DRX) cycle which instructs the UEto access the S-Cell during the determined time window.

In example 3, the subject matter of any one or more of examples 1-2 mayoptionally include wherein the indication is located in a PhysicalDownlink Control Channel (PDCCH).

In example 4, the subject matter of any one or more of examples 1-3 mayoptionally include wherein the indication is a bit field in the PDCCH.

In example 5, the subject matter of any one or more of examples 1-4 mayoptionally include wherein the operations of sending the indicationcomprises building the PDCCH by scrambling a Cyclic Redundancy Checkfield of the PDCCH using a predetermined Radio Network TemporaryIdentifier (RNTI) that indicates that the unlicensed frequency band isavailable for use by the S-CELL.

In example 6, the subject matter of any one or more of examples 1-5 mayoptionally include wherein the operations of sending the indicationcomprises scheduling a Physical Downlink Shared Channel (PDSCH) of theS-Cell on the PDCCH, the PDCCH sent on the P-Cell.

In example 7, the subject matter of any one or more of examples 1-6 mayoptionally include wherein the operations of sending the indicationcomprises scheduling a Physical Downlink Shared Channel (PDSCH) of theS-Cell on the PDCCH, the PDCCH sent on the S-Cell.

In example 8, the subject matter of any one or more of examples 1-7 mayoptionally include wherein the indication is located in a PhysicalHybrid-ARQ Indicator Channel (PHICH).

In example 9, the subject matter of any one or more of examples 1-8 mayoptionally include wherein the indication is located in a beacon signal.

In example 10, the subject matter of any one or more of examples 1-9 mayoptionally include wherein the at least a portion of the determined timewindow is the entire determined time window.

In example 11, the subject matter of any one or more of examples 1-10may optionally include wherein the operations of providing the S-Cellcomprise providing the S-Cell only in the determined timeslot and in oneor more other successive timeslots.

In example 12, the subject matter of any one or more of examples 1-11may optionally include wherein the determined time window is configuredin a cell specific manner.

Example 13 includes or may optionally be combined with the subjectmatter of any one of examples 1-12 to include subject matter (such as aeNodeB, device, apparatus, or machine) comprising hardware processingcircuitry configured to: provide a P-Cell on a primary frequency band;determine that a secondary frequency band is available for use by asecondary cell (S-Cell) during a time slot; transmit an indication to aUE that the S-Cell is available for association during the time slot;and provide the S-Cell during the time slot, the S-Cell including a datachannel.

In example 14, the subject matter of any one or more of examples 1-13may optionally include wherein the indication is a Radio ResourceControl (RRC) message specifying a Discontinuous Reception (DRX) cyclewhich instructs the UE to access the S-Cell during the determined timeslot.

In example 15, the subject matter of any one or more of examples 1-14may optionally include wherein the indication is located in a PhysicalDownlink Control Channel (PDCCH).

In example 16, the subject matter of any one or more of examples 1-15may optionally include wherein the indication is a bit field in thePDCCH.

In example 17, the subject matter of any one or more of examples 1-16may optionally include wherein the hardware processing circuitry is tosend the indication by at least building the PDCCH by scrambling aCyclic Redundancy Check field of the PDCCH using a predetermined RadioNetwork Temporary Identifier (RNTI) that indicates that the unlicensedfrequency band is available for use by the S-CELL.

In example 18, the subject matter of any one or more of examples 1-17may optionally include wherein the hardware processing circuitry is tosend the indication by at least scheduling a Physical Downlink SharedChannel (PDSCH) of the S-Cell on the PDCCH, the PDCCH sent on theP-Cell.

In example 19, the subject matter of any one or more of examples 1-18may optionally include wherein the hardware processing circuitry is tosend the indication by at least scheduling a Physical Downlink SharedChannel (PDSCH) of the S-Cell on the PDCCH, the PDCCH sent on theS-Cell.

In example 20, the subject matter of any one or more of examples 1-19may optionally include wherein the indication is located in a PhysicalHybrid-ARQ Indicator Channel (PHICH).

In example 21, the subject matter of any one or more of examples 1-20may optionally include wherein the indication is located in a beaconsignal.

In example 22, the subject matter of any one or more of examples 1-21may optionally include wherein the at least a portion of the determinedtimeslot is the entire determined timeslot.

In example 23, the subject matter of any one or more of examples 1-22may optionally include wherein the S-Cell is only provided in thedetermined timeslot and in one or more other successive timeslots.

In example 24, the subject matter of any one or more of examples 1-23may optionally include wherein the determined timeslot is configured ina cell specific manner.

Example 25 includes or may optionally be combined with the subjectmatter of any one of examples 1-24 to include subject matter (such as aUE, device, apparatus, or machine) comprising: hardware processingcircuitry configured to: associate with a P-Cell on a licensed frequencyband provided by an eNodeB; receive an indication on the P-Cell that asecondary-cell (S-Cell) is available on an unlicensed frequency band ata particular time period; associate with the S-Cell on the unlicensedfrequency band for the particular time period, the S-Cell provided bythe eNodeB.

In example 26, the subject matter of any one or more of examples 1-24may optionally include wherein the indication is a Radio ResourceControl (RRC) message specifying a Discontinuous Reception (DRX) cycle.

In example 27, the subject matter of any one or more of examples 1-26may optionally include wherein the indication is located in a PhysicalDownlink Control Channel (PDCCH).

In example 28, the subject matter of any one or more of examples 1-27may optionally include wherein the indication is a bit field in thePDCCH.

In example 29, the subject matter of any one or more of examples 1-24may optionally include wherein the indication is the use of a particularRadio Network Temporary Identifier (RNTI) to scramble a CyclicRedundancy Check (CRC) of the PDCCH.

In example 30, the subject matter of any one or more of examples 1-29may optionally include wherein the indication is the eNodeB scheduling aPhysical Downlink Shared Channel (PDSCH) of the S-Cell on the PDCCH, thePDCCH being received on the P-Cell.

In example 30, the subject matter of any one or more of examples 1-29may optionally include wherein the indication is the eNodeB scheduling aPhysical Downlink Shared Channel (PDSCH) of the S-Cell on the PDCCH, thePDCCH being received on the S-Cell.

In example 31, the subject matter of any one or more of examples 1-30may optionally include wherein the indication is located in a PhysicalHybrid-Automatic Repeat Request (ARQ) Indicator Channel (PHICH).

In example 32, the subject matter of any one or more of examples 1-31may optionally include wherein the indication is located in a beaconsignal.

Example 33 includes or may optionally be combined with the subjectmatter of any one of examples 1-32 to include subject matter (such as amethod, means for performing acts, a machine readable medium includinginstructions for performing operations) for accessing a cell comprising:at a user equipment (UE): associating with a P-Cell on a licensedfrequency band provided by an eNodeB; receiving an indication on theP-Cell that a secondary-cell (S-Cell) is available on an unlicensedfrequency band at a particular time period; associating with the S-Cellon the unlicensed frequency band for the particular time period, theS-Cell provided by the eNodeB.

In example 35, the subject matter of any one or more of examples 1-34may optionally include wherein the indication is a Radio ResourceControl (RRC) message specifying a Discontinuous Reception (DRX) cycle.

In example 36, the subject matter of any one or more of examples 1-35may optionally include wherein the indication is located in a PhysicalDownlink Control Channel (PDCCH).

In example 37, the subject matter of any one or more of examples 1-36may optionally include wherein the indication is a bit field in thePDCCH.

In example 38, the subject matter of any one or more of examples 1-37may optionally include wherein the indication is the use of a particularRadio Network Temporary Identifier (RNTI) to scramble a CyclicRedundancy Check (CRC) of the PDCCH.

In example 39, the subject matter of any one or more of examples 1-38may optionally include wherein the indication is the eNodeB scheduling aPhysical Downlink Shared Channel (PDSCH) of the S-Cell on the PDCCH, thePDCCH being received on the P-Cell.

In example 40, the subject matter of any one or more of examples 1-39may optionally include wherein the indication is the eNodeB scheduling aPhysical Downlink Shared Channel (PDSCH) of the S-Cell on the PDCCH, thePDCCH being received on the S-Cell.

In example 41, the subject matter of any one or more of examples 1-40may optionally include wherein the indication is located in a PhysicalHybrid-Automatic Repeat Request (ARQ) Indicator Channel (PHICH).

In example 42, the subject matter of any one or more of examples 1-41may optionally include wherein the indication is located in a beaconsignal.

What is claimed is:
 1. An apparatus of an evolved Node B (eNB), theapparatus comprising: memory; and processing circuitry, the processingcircuitry configured to: provide a primary cell (P-Cell) on a primaryfrequency band; determine that a secondary frequency band is availablefor use by a secondary cell (S-Cell), wherein the second frequency bandis different than the primary frequency band; encode an informationfield in a Physical Downlink Control Channel (PDCCH) for transmission toa User Equipment (UE) on the P-Cell, the information field indicatingthat the S-Cell is available during a specified period of time; andprovide the S-Cell during the specified period of time, the S-Cellincluding a data channel.
 2. The apparatus of claim 1, wherein theprocessing circuitry is configured to: encode the information field inthe PDCCH for transmission to the UE on the S-Cell.
 3. The apparatus ofclaim 1, wherein the processing circuitry is configured to: encode asecond information field in the PDCCH for transmission to the UE, thesecond information field indicating that the S-Cell is not availableduring a second specified period of time.
 4. The apparatus of claim 3,wherein the processing circuitry is configured to: encode the secondinformation field in the PDCCH for transmission to the UE on the S-Cell.5. The apparatus of claim 1, wherein the information field comprises abinary value, indicating whether the S-Cell is currently available. 6.The apparatus of claim 1, wherein the information field comprises abinary value, indicating whether the S-Cell is available during thespecified period of time.
 7. The apparatus of claim 1, wherein theprocessing circuitry is configured to: select a Radio Network TemporaryIdentifier (RNTI) from a plurality of available RNTIs, the selected RNTIindicating current availability of the S-Cell.
 8. The apparatus of claim7, wherein the processing circuitry is configured to: scramble a CyclicRedundancy Check (CRC) field in the PDCCH using the selected RNTI, thescrambled CRC and the selected RNTI for transmission to the UE,indicating to the UE the current availability of the S-Cell based on theselected RNTI.
 9. The apparatus of claim 8, wherein an absence of aparticular RNTI from the scrambled CRC transmission to the UE indicatescurrent unavailability of the S-Cell.
 10. The apparatus of claim 1,wherein the processing circuitry is configured to: select a RadioNetwork Temporary Identifier (RNTI) from a plurality of available RNTIs,the selected RNTI indicating current unavailability of the S-Cell. 11.The apparatus of claim 10, wherein the processing circuitry isconfigured to: scramble a Cyclic Redundancy Check (CRC) field in thePDCCH using the selected RNTI, the scrambled CRC and the selected RNTIfor transmission to the UE, indicating to the UE the currentunavailability of the S-Cell based on the selected RNTI.
 12. Theapparatus of claim 11, wherein an absence of a particular RNTI from thescrambled CRC transmission to the UE indicates current availability ofthe S-Cell.
 13. The apparatus of claim 1, wherein the S-Cell is onlyprovided in a determined timeslot and in one or more other successivetimeslots.
 14. The apparatus of claim 13, wherein the determinedtimeslot is configured in a cell specific manner.
 15. The apparatus ofclaim 1, wherein the processing circuitry comprises a basebandprocessor.
 16. The apparatus of claim 1, further comprising atransceiver coupled to one or more antennas, the transceiver configuredto transmit to the UE the encoded information field in the PDCCH.
 17. Anon-transitory machine-readable medium that stores instructions whichwhen performed by a machine, cause the machine to perform operations forsignaling a User Equipment (UE) when a cell is available in anunlicensed frequency band, the operations comprising: providing aprimary cell (P-Cell) on a licensed frequency band; determining that anunlicensed frequency band is available for use by a secondary cell(S-Cell) for a determined time window; encoding an indication in aPhysical Downlink Control Channel (PDCCH) for transmission to a UserEquipment (UE) on the P-Cell, that the S-Cell is available for use bythe UE for at least a portion of the determined time window; andproviding the S-Cell in the unlicensed frequency band for the determinedtime window.
 18. The machine-readable medium of claim 17, wherein thedetermined time window is associated with a current or future timeperiod with a determined timing boundary.
 19. The machine-readablemedium of claim 17, wherein the indication comprises a bit field in thePDCCH, the bit field indicating whether the S-Cell is currentlyavailable.
 20. The machine-readable medium of claim 17, wherein theindication comprises a bit field in the PDCCH, the bit field indicatingwhether the S-Cell is available during the determined time window. 21.The machine-readable medium of claim 17, wherein the operations ofencoding the indication comprises building the PDCCH by scrambling aCyclic Redundancy Check field of the PDCCH using a predetermined RadioNetwork Temporary Identifier (RNTI) that indicates that the unlicensedfrequency band is available for use by the S-CELL.
 22. An apparatus of auser equipment (UE), the apparatus comprising: memory; and hardwareprocessing circuitry, the hardware processing circuitry configured to:associate with a primary cell (P-Cell) on a licensed frequency bandprovided by an Evolved Node-B (eNB); decode an information fieldreceived from the eNB in a Physical Downlink Control Channel (PDCCH) ofthe P-Cell, the information field indicating that a secondary cell(S-Cell) is available on an unlicensed frequency band during a specifiedperiod of time; and associate with the S-Cell on the unlicensedfrequency band for the specified period of time, the S-Cell provided bythe eNB.
 23. The apparatus of claim 22, wherein the information fieldcomprises a binary value, indicating that the S-Cell is currentlyavailable for association.
 24. The apparatus of claim 22, wherein theinformation field comprises a binary value, indicating that the S-Cellis unavailable during a second specified period of time.
 25. Theapparatus of claim 22, wherein the processing circuitry is configuredto: decode a second information field received from the eNB in aPhysical Downlink Control Channel (PDCCH) of the S-Cell, the secondinformation field indicating that the S-Cell is available on anunlicensed frequency band during a second specified period of time.